the personal blog of yan/@bcrypt
1. A perfect game-theoretic analysis machine Imagine that you had a magic machine. You tell the machine what your goals are. The machine tells you, in any situation, the optimal statement to say in order to achieve your goals, and who to say it to. The statement may or may not be true.
Under which circumstances, if any, would you follow the machine’s instructions?
Example 1: Bob tells the machine that his goal is to become as rich as possible.
[Update (12/14/16): Reuters has specified that the rootkit was implemented as a Linux kernel module. Wow.]
Yesterday morning, Reuters dropped a news story revealing that Yahoo installed a backdoor on their own infrastructure in 2015 in compliance with a secret order from either the FBI or the NSA. While we all know that the US government routinely asks tech companies for surveillance help, a couple aspects of the Yahoo story stand out:
While migrating my blog from WordPress to Hugo + GitHub Pages, I found two old diary entries from last autumn, a period of life when I rode buses a lot. They are copied below.
oct 28, 2015 they told me not to, so i’m taking the bus from downtown LA to LAX. on my right, a man is asking everyone except me for 50 cents. everyone except me is a black guy.
The second and last time that I visit Chelsea Manning, we speak and move with a sense of urgency, as if a natural disaster is imminent. By now, the Ft Leavenworth prison visit procedure feels strangely familiar, like a movie you once watched in a dream. I check in with the uniformed officer at the Disciplinary Barracks’ front desk, wait uselessly while he misgenders Chelsea and figures out if I’m allowed to visit her, rent a locker to stow my jacket which is prohibited in the visit room (due to the having of zippers), don an unsuspicious smile when the guard tries to deny something i’m bringing (this time, it’s blank drawing paper and pencils – both of which are eventually let through), pass through the metal detector and double-doored atrium, wait for the guard to let Chelsea through the opposite doors, hug briefly, sit down at her favorite table against the wall, buy her snacks from the vending machines twice (first course: Dr.
On the day that I am scheduled to see my friend Chelsea for the first time in six years, I wake up at 4:51pm to a shrieking fire alarm in my hotel room. Semi-conscious and disoriented, I leap out of bed and spin around wildly grabbing at all the things I care about – my phone and passport, the precious slip of paper that will allow me entrance to Fort Leavenworth prison, the bag of quarters that Chelsea asked me to bring – ready for an FBI raid disguised as a fire drill.
i turn 25 in an hour. this seems strange and unbelievable. surely 25 years of existence is enough to become acquainted with the monotonicity of time. but instead the seconds pass and disbelief stares back, unmoving. a quarter-century is a long time. with sadness, i realize how much of it i have forgotten already. imagine that we could live forever. would we still talk about wasting time if time were an unlimited resource?
You probably don’t remember me, but we met in September 2009. This was before everyone knew your name and before many people knew mine.
I was at home, helping my friend cut her hair. Out of the corner of my eye, I saw you walk into the living room. You were taking photos of our mural-covered walls, seemingly happy to be in such a bizarre and interesting house of MIT students.
Every so often, I get sick of basically everything. Walls become suffocating, routine is insufferable, and the city I live in wraps itself against the sky like a cage. So inevitably I duck away and find something to chase (warm faces, the light in autumn, half-formed schemes, etc.), run until I’m dizzy and lost and can’t remember whose couch I’m waking up on or why I crashed there. Weeks later, the sky bruises into swollen dusk, some familiar voice yells for me to come home so I run back into my bed once again, wondering if home is this place more than it is the feeling of staring at an unfamiliar timetable and noticing your heartbeat quicken.
you know things are getting better when you walk away from the hotel where you just gave two presentations wearing your best pretense of holding-it-togetherness while inside you felt shakey, hungover, and insane. remember how long you stood there, smiling and rationing weak handshakes while pretending you believed that you had a future? promise yourself you’re never doing that again. you walk away from the volatile company of people who made you feel shitty about yourself without trying to and into the car of someone who looks like they could be your new friend.
In addition to unforgettable life experiences and personal growth, one thing I got out of DEF CON 23 was a copy of POC||GTFO 0x08 from Travis Goodspeed. The coolest article I’ve read so far in it is “Deniable Backdoors Using Compiler Bugs,” in which the authors abused a pre-existing bug in CLANG to create a backdoored version of sudo that allowed any user to gain root access. This is very sneaky, because nobody could prove that their patch to sudo was a backdoor by examining the source code; instead, the privilege escalation backdoor is inserted at compile-time by certain (buggy) versions of CLANG.